X ray fills the gap

X-ray lithography has been used in mix and match mode with optical steppers to build test circuits in support of DRAM and Logic development at IBM's Advanced Semiconductor Technology Center, ASTC. Prior to building the test devices, hundreds of wafers were exposed using x-ray lithography to define the etch processes for critical levels and to help separate optical lithography, resist and etching effects. The demand for this type of support required IBM's Advanced Lithography Facility (ALF) to focus on a set of pilot line issues not previously faced by this emerging lithography. The challenges and solutions which resulted are discussed. This paper examines the requirements for the introduction of x-ray into pilot line use based on ALF's most recent experience and performance.